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Objective To evaluate biomechanical properties of the nickel-titanium (NiTi) memory alloy stent and its in vitro biomechanical properties for lumbar interbody fusion. Methods The mechanical properties of the NiTi memory alloy stent were tested on mechanical testing machine. Moreover, lumbar interbody fusion was simulated on fresh lumbar specimens, and biomechanical properties of the NiTi memory alloy stent with matching bone graft for used for lumbar interbody fusion were analyzed and compared with the traditional box-shape cage. Results The maximum compressive strength of the NiTi memory alloy stent was ( 12 964 ± 962) N. The maximum deformation within the effective range of memory characteristics was (4. 68±0. 03) mm. The recovery rate of the NiTi memory alloy stent was up to 99. 86% . Compared with the intact lumbar model, the stability of the operative segment after the simulated lumbar interbody fusion using NiTi memory alloy stent alone was increased in the direction of anterior flexion, posterior extension, lateral flexion and rotation, which was equivalent to the box shape cage group (P>0. 05). After the combined use of autogenous bone granule and absorbable bone cement the ROM of the operative segment was further reduced (P0. 05). The pull-out strength of the NiTi memory alloy stent with matching bone graft group was significantly stronger than that of the box-shape cage group (P<0. 05). Conclusions The NiTi memory alloy stent in this study was designed with a matched bone granule-absorbable bone cement graft,which provided a new idea for the further optimization and development of lumbar interbody fusion. With excellent support and deformation properties, this NiTi memory alloy stent is biomechanical equivalent to the traditional box shape cage for lumbar interbody fusion, and can greatly improve the stability of surgical segment and the pull-out strength of implants after the combined use of autogenous bone granule and absorbable bone cement.
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Objective Aiming at the clinical problem of the low matching degree with the patient’s anatomical morphology for traditional cervical fusion cage, a cervical fusion cage with the function of adjustable height and the shape matched with the vertebral body was established, and its biomechanical properties were evaluated. Methods A cervical C4-5 segment fusion model was established according to anterior cervical discectomy and fusion (ACDF), so as to simulate different motion conditions, i.e. anterior flexion, posterior extension, left/right lateral flexion, left/right rotation, and stress of the fusion cage and vertebral endplate was calculated. After three-dimensional (3D) printing of the fusion cage, an in vitro mechanical experiment was conducted to explore safety and stability of the fusion cage. ResultsThe fusion cage could keep the range of motion (ROM) of cervical vertebrae at the fusion segment with 1°-2.8° and reduce the ROM to 40%-80% of the natural segment. In the in vitro compression test, the yield load of the fusion cage was (2 721.67±209) N, which met the maximum demand of the physiological load in service state. Conclusions The designed fusion device with adjustable height shows better biomechanical properties and can reduce the selection step in operation.
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Spinal fusion is a standard operation for treating moderate and severe intervertebral disc diseases. In recent years, the proportion of three-dimensional printing interbody fusion cage in spinal fusion surgery has gradually increased. In this paper, the research progress of molding technology and materials used in three-dimensional printing interbody fusion cage at present is summarized. Then, according to structure layout, three-dimensional printing interbody fusion cages are classified into five types: solid-porous-solid (SPS) type, solid-porous-frame (SPF) type, frame-porous-frame (FPF) type, whole porous cage (WPC) type and others. The optimization process of three-dimensional printing interbody fusion cage and the advantages and disadvantages of each type are analyzed and summarized in depth. The clinical application of various types of 3D printed interbody fusion cage was introduced and summarized later. Lastly, combined with the latest research progress and achievements, the future research direction of three-dimensional printing interbody fusion cage in molding technology, application materials and coating materials is prospected in order to provide some reference for scholars engaged in interbody fusion cage research and application.
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Humans , Intervertebral Disc Degeneration , Intervertebral Disc Displacement , Porosity , Printing, Three-Dimensional , Spinal FusionABSTRACT
BACKGROUND: The incidence of lumbar spinal stenosis with vertebral instability is increasing year by year, which can cause symptoms such as waist and leg pain, lower limbs feeling numbness and intermittent claudication. In recent years, scholars have tried various minimally invasive treatment methods to further reduce the trauma and complications of surgery. The improvement of the clinical effect of minimally invasive surgery for lumbar spinal stenosis with vertebral instability is an important issue to be solved. OBJECTIVE: To evaluate the mid-long-term effect of only placed expandable interbody fusion cage in the treatment of lumbar spinal stenosis with vertebral instability using micro-endoscopic discectomy system. METHODS: A retrospective, self-control clinical trial was conducted in the First Affiliated Hospital of Zhengzhou University from 2012 to 2014. Totally 35 patients with lumbar spinal stenosis combined with vertebral instability were treated by only placed expandable interbody fusion cage using micro-endoscopic discectomy system. This study was approved by the Ethics Committee of the First Affiliated Hospital of Zhengzhou University. RESULTS AND CONCLUSION: (1) All 35 patients were followed-up for 60-85 months, mean (70.17±5.40) months. Among these patients, lumbar interbody fusion in 1 segment, 2 segments and 3 segments was performed in 6, 20 and 9 cases, respectively. A total of 73 intervertebral spaces were fused. (2) The mean operation time was 53.49±9.13 minutes (range, 35-75 minutes). The mean blood loss was 114.86±54.23 mL (range, 50-250 mL). (3) Dural rupture occurred in one case during operation and then hypotensive cranial pressure headache occurred after operation. Headache gradually eased after the patient received rehydration and analgesic treatment for 3 days. Poor incision healing occurred in one case after operation and then healed well after one-week vacuum sealing drainage technique. (4) The Visual Analogue Scale scores, Oswestry Disability Index, and height of intervertebral space were significantly decreased at 1 week, 6 months, 1 year, 2 years after surgery and the final follow-up compared to the preoperative ones. At 6 months after the operation, 31(42.5%) intervertebral spaces reached a strong fusion, 25(34.2%) possible fusion, and 17(23.3%) did not reach fusion. At 1 year after surgery, 51(69.9%) intervertebral spaces achieved a strong fusion and 22(30.1%) achieved possible fusion. At 2 years after surgery, 57(78.1%) intervertebral spaces achieved a strong fusion and 16(21.9%) achieved possible fusion. During final follow-up, 62(84.9%) intervertebral spaces achieved a strong fusion and 11(15.1%) achieved possible fusion. (5) At the last follow-up, cage migration was found in one case. The patient was not treated because of symptomless. (6) Unilateral approach only placed expandable interbody fusion cage by using micro-endoscopic discectomy system is a safe and reliable minimally surgical method, which has a good mid-long-term effect on lumbar spinal stenosis with vertebral instability.
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BACKGROUND: Recent clinical studies have found that during the implantation of biomaterials, the internal environment of the body will change to a certain extent, and different levels of immunity and stress responses will occur. There are also obvious differences in the immune and stress responses of different biological materials. OBJECTIVE: To investigate the effect of 3D printed interbody fusion cage on patients with cervical spondylosis of spinal cord type and its effect on serum cortisol and norepinephrine levels. METHODS: Sixty-three patients with cervical spondylotic myelopathy who were admitted to the Affiliated Hospital of Chengde Medical University from July 2015 to July 2018 were selected, including 40 males and 23 females, aged 30-78 years old. The patients were randomly divided into a research group (n=31) and a control group (n=32) according to a random number table. All patients received anterior cervical decompression and bone graft fusion and internal fixation. Patients in the research group were implanted with 3D printed intervertebral fusion cage during operation. The patients in the control group were implanted with polyetheretherketone interbody fusion cage and allogeneic bone. The operation and complications of the two groups were compared. Serum cortisol and norepinephrine levels were detected before and 1 and 3 days after operation. Cervical curvature and intervertebral height were measured before surgery, 1 week, and 6 months after surgery. Axial symptoms were counted at 6 months after surgery. The trial was approved by the Ethics Committee of the Affiliated Hospital of Chengde Medical University. RESULTS AND CONCLUSION: (1) Operation time, intraoperative blood loss and hospitalization time were not significantly different between the two groups (P > 0.05). (2) Among 31 cases, there were 1 case of screw loosening and 1 case of implant movement in the research group. Among 32 cases, there were 3 cases of screw loosening, 3 cases of immune rejection, 2 cases of implant movement, and 1 case of implant collapse in the control group. The incidence of complications was lower in the research group than that in the control group (P < 0.05). (3) At 1 and 3 days after operation, the levels of cortisol and norepinephrine were higher in both groups than those before surgery (P < 0.05), but above levels were lower in the research group than in the control group (P < 0.001). (4) The cervical curvature and intervertebral height at 1 week and 6 months after operation in both groups were higher than those before surgery (P < 0.05), and above indexes were higher in the research group than in the control group (P < 0.05). (5) The axial symptom in the research group was lighter than that in the control group at 6 months after operation (P < 0.05). (6) The results show that the application of 3D printed interbody fusion cage to cervical spondylotic myelopathy can reduce complications, promote the recovery of cervical curvature and intervertebral height, and improve the stability of cervical spine, and the body’s stress response and axial symptoms are mild.
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Objective At present, the mainstream surgical mode and the gold standard for the treatment of spine related diseases are still the intervertebral fusion with the intervertebral implantation of the intervertebral fusion device.The intervertebral fusion device routinely used in clinical practice cannot degrade in vivo after implantation, resulting in lifelong foreign body.High elastic modulus also leads to osteoporosis in adjacent vertebral bodies, which leads to implant sinking, stress shielding and'pseudomorphism'of fusion.The ideal biodegradable synthetic intervertebral fusion cage can be progressively degraded and eventually replaced by new bone, which has the advantages of elastic modulus close to cortical bone, good biocompatibility, X-ray permeability and good initial mechanical strength.In this paper, animal analysis of biodegradable intervertebral fusion cage, clinical effect analysis, current shortcomings and future trends were reviewed.
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Objective To investigate the influence of ROI-C cervical implantation in the C5-6 segment on the C3-7 range-of-motion (ROM), biomechanical properties of the intervertebral disc and the vertebral body, and the mode of force transmission. Methods Two types of surgeries, ROI-C implantation and autograft fusion with plate fixation, were considered to establish the finite element model of cervical C5-6 segment degeneration. The ROM of C3-7 during flexion, extension, lateral bending, and axial rotation, as well as stress distributions on the adjacent discs, vertebral body, and implanted devices under two procedures, were analyzed. Results ROI-C implantation had a relatively small influence on the ROM of the adjacent segment. The stress on the vertebral discs was reduced, but the stress on the vertebral body increased significantly, with the C5 vertebral body stress increasing by 251%. In the fusion surgery model, the ROM of the surgical segment was reduced by 86%-91%, while the ROM of the adjacent segments and the stress on the vertebral disc and vertebral body increased significantly. Conclusions ROI-C implantation surgery has a relatively small influence on the cervical ROM and the intervertebral disc, and it has a greater impact on the vertebral body. The research findings provide a theoretical basis for the design of operation plans and clinical studies on ROI-C implantation and autograft fusion with plate fixation.
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Objective To evaluate the clinical outcome of artificial cervical disc arthroplasty combined with anchoring cervical intervertebral fusion cage (ACIFC) in the treatment of multilevel cervical disc herniation. Methods From October 2011 to September 2013, 0.26 patients with multilevel cervical disc herniation underwent artificial cervical disc arthroplasty combined with ACIFC, there were 10 male and 16 female with age from 32 to 60 years (mean 46.8 years). Two segment were involved in 15 patients, three segment were involved in 11 patients. Neck disability index (NDI) and Japanese Orthopaedic Association (JOA) score were used to evaluate neurofunctional recovery preoperatively and postoperatively. The postoperative stabilization and the range of motion (ROM) of implanted disc and the fusion of cage were observed on dynamic radiograph. Results The average operation time and amount of bleeding were (95±15) min and (100±20) ml respectively. The average postoperative follow-up was 15 months(range 6-20 months). At the end of follow up,the scores of JOA was increased and the scores of NDI was decreased:(9.08±1.72) scores vs. (14.88±1.37) scores, (40.31±4.97) scores vs. (25.23±4.10) scores,there had significant differences (P0.05). Solid fusion was achieved in all levels brought by cage.There was no cage subsidence or displacement. All artificial cervical disc achieved definite stabilization, no intraoperative and postoperative complication was noted. Conclusions Artificial cervical disc arthroplasty combined with ACIFC provides a feasible way for the treatment of multilevel cervical disc herniation. The definite stabilization and maintained ROM can reduce the fusion segments and avoid the increased stress of adjacent segment which can ensure a good preliminary clinical outcome.
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objective To introduce the design concept and structure of a new type of lumbar intervertebral fusion cage ,and to e-valuate its biomechanical properties .Method A partially bioasorbable interbody fusion cage(PBIFC) made of nano hydroxyapatite and poly amino acid /calcium sulfate copolymer materials was developed .Range of motion(ROM ) ,compressive load ,and pull-out test on flexion ,extension ,lateral bending ,and torsion moment on fresh calf L3/L4 specimens of functional spinal union were carried out of iliac bone group ,PBIFC group ,and nano hydroxyapatite/polyamide 66(nHA/PA66) group .Result Of each movement ,the ROM value of iliac bone group are higher than the other two groups ,the difference was statistically significant (P0 .05) .The pull-out strength of PB-IFC group are higher than iliac bone group ,and the difference was statistically significant (P0 .05) .The compressive load of iliac bone group was lower than that of two cage group ,the difference was statistically significant (P0 .05) .Conclusion With good implant stability ,pull-out resistance ,and compression resistance performance ,PBIFC can meet the biomechanics requirements of clinical implant .
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Objective To analyze the clinical feasibility of unilateral transforaminal lumbar interbody fusion (TLIF) for treating lumbar degenerative diseases by finite element method. Methods Based on CT scan data, three-dimensional (3D) finite element models of the normal L3-5 segments under physiological status (intact lumbar model), L4/5 with unilateral pedicle screw fixation plus interbody fusion (unilateral TLIF model) and L4/5 with bilateral pedicle screw fixation plus interbody fusion (bilateral TLIF model) were established by using Mimics, Pro/E, ANSYS software, respectively. Preload of 500 N and load of 10 N•m torque were applied on the superior surface of the L3 segment to simulate 5 physiological activities: body upright, flexion, extension, left lateral bending and right axial rotation. The deformation and stress distributions in vertebral body, vertebral discs, pedicle screw and cage under different loads were then recorded and analyzed to compare mechanical properties of the two fixation methods. Results The deformation of L3-5 segments fixed with unilateral TLIF or bilateral TLIF decreased as compared to the intact lumbar model; the stresses in cage reached the maximum in both unilateral TLIF model and bilateral TLIF model during back extension, meanwhile peak stresses on pedicle screws in unilateral TLIF were significantly higher than those on bilateral TILF model, with the peak stress of 463.39 MPa during back extension. ConclusionsUnilateral TLIF can be selected as a method for treating lumbar degenerative diseases; however, its stability was inferior to bilateral TLIF due to the higher peak stress. Therefore, less stretch exercises may be safe for patients during rehabilitation to avoid surgery failure or pedicle screw fracture.
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BACKGROUND:There are various commonly used interbody fusion methods, such as autologous bone, al ograft bone and titanium-based posterior lumbar interbody fusion, and each method has its own advantages and disadvantages. OBJECTIVE:To observe the clinical efficacy of a bioactive nano-hydroxyapatite/polyamide 66 fusion cage in posterior lumbar interbody fusion for the treatment of lumbar disease. METHODS:A retrospective case analysis was conducted on 16 cases treated with posterior lumbar interbody fusion at the Department of Orthopedic, the First Affiliated Hospital of Gannan Medical University from July 2010 to December 2011, and al the patients were implanted with nano-hydroxyapatite/polyamide 66 biological activity fusion cage. RESULTS AND CONCLUSION:Al the patients were fol owed-up for 10-24 months, and the lumbar pain was significant improved, the lumbar visual analogue score, lumbar Japanese Orthopaedic Association score and Oswestry disability index score were significantly improved during the final fol ow-up period (Pfusion without nano-hydroxyapatite/polyamide 66 fusion cage displacement or subsidence. The results indicate that nano-hydroxyapatite/polyamide 66 fusion cage for the treatment of posterior lumbar interbody fusion can reconstruct the lumbar stability and provide immediate stability after implantation, and has good biological activity.
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[Objective] The objective of the study was to determine the clinical and radiological outcomes of cervical interbody fusion using ROI cages. [Methods] Patients showing degenerative cervical mono- or bi-level pathology were prospectively included. Using AP and lateral radiographs, segmental height of the treated segments was determined quantitatively. Cage characteristics were described qualitatively. Clinical data such as the neck disability in-dex(NDI), numeric rating scale(NRS) were col ected at al time points .[Results] The scores of NDI, NRS were decreased gradual y, and stable after half year;but they were respectively reduced to 8.64 and 1.57 from 23.32 and 8.93, with difference of statistical meaning. The intervertebral angle increased af-ter operation, then decreased gradual y and was stable after half year, was 3.6 °after 1 year. The intervertebral height was maximum after operation, then re-duced gradual y, and was 5.32mm or so after 1 year. 16 patients were al cured after 1 year, with short fusion rate reaching 100%. [Conclusions] The clini-cal and radiological short-term outcome of anterior cervical discectomy and fusion using ROI cage are excel ent.
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ObjectiveTo evaluate the mid-term clinical effect of nano-hydroxyapatite and polyamide 66 (n-HA/PA66) intervertebral fusion cage in treatment of thoracolumbar burst fractures.Methods A total of 87 patients with thoracolumbar burst fractures were managed by thoracolumbar body resection combined with n-HA/PA66 intervertebral fusion cage from December 2007 to September 2008.The clinical effect, safety and radiographic outcomes were evaluated.Results No nerve damage was deteriorated in all the patients.The neural function was improved for 1-2 grade except for four patients at Frankel grade A.The patients were followed up for mean 21.3 months (17-24 months).The kyphosis was (14.4 ± 12.6)° preoperatively, (3.7 ± 8.7) ° immediately after surgery and (4.0 ± 8.3)° at final follow-up.The distance between the upper and lower vertebral bodies was (96.9 ± 17.2) mm preoperatively, (109.5 ± 17.1) mm immediately after surgery and (108.3 ± 16.4) mm at final follow-up.No cage replacement, internal fixation breakage or neurologic impairment were observed during follow-up period.There were 58 patients with grade E fusion, 22 with grade D fusion and 7 with grade C fusion.ConclusionsAnterior decompression combined with n-HA/PA66 intervertebral fusion cage is an effective method for treatment of thoracolumbar burst fracture.The kyphosis is rectified and the intervertebral distance is corrected, with a high rate of fusion.
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PURPOSE: To evaluate the clinical and radiologic efficacy of posterior lumbar interbody fusion (PLIF) using a threaded fusion cage (TFC) alone with autogenous iliac corticocancellous bone graft for single-level degenerative lumbar spinal disorders. MATERIALS AND METHODS: Thirty-eight consecutive patients receiving PLIF with TFC alone were evaluated with at least three years of follow-up. Clinical outcome and satisfaction were assessed using Ragab's measurements. Radiological outcomes were analyzed in terms of lumbar lordosis, segmental lordosis, disc height, and fusion rates. RESULTS: Disc height was 6.18+/-2.54 mm, 11.71+/-1.60 mm and 9.94+/-1.94 mm on average for preoperative, postoperative, and final follow-up, respectively. Lumbar lordosis was 27.46+/-11.47degrees, 31.41+/-8.89degrees on average for preoperative and at final follow-up, respectively. Segmental lordosis was 11.51+/-9.35degrees preoperatively, and 10.86+/-7.49degrees at final follow-up. Satisfactory clinical outcome were obtained in 89.2% of patients with successful bone fusion in 73.0% of patients. CONCLUSION: Stand alone TFC is an effective treatment modality in maintenance of disc height and lumbar lordosis, with satisfactory long term clinical outcomes in the treatment of single-level degenerative lumbar spinal disorders.
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Animals , Humans , Follow-Up Studies , Lordosis , TransplantsABSTRACT
[Objective]To evaluate the curative effect,indication and care for cage,the patients with lumbar vertebrae instability were treated by 1umbar interbody ecstatic fusion cage.[Method]There were 42 patients,male 31 and female 11,aged 3 5~78 years(averaged 46 years) and suffered with spondylolisthesis of isthmus non-union in 26 cases and degenerative spondylolisthsis in 1 6 cases,including spondylolisthsis of L3、4 5 cases,of L4、5 23 cases and of L5S1 14 cases.According to Meyerding classification,there were grade-I spondylolisthsis 29 cases and grade-Ⅱ 13 cases.All patients were treated with decompression of lumbar canal,resection of vertebral disc,insertion of ecstatic fusion cage.The curative effect was observed and evaluated.[Result]Patients were followed up for 6 months to 6 years,the results were good rate of JOA scores 95%,the recovery rate of inter-spinal height,reduction and bone fusion rate were up to 98%.[Conclusion]For lumbar spondylolisthesis of grade Ⅰ～Ⅱ,the ecstatic fusion cage has good effect on recovery of inter-spinal height,improvement of bone fusion rate,maintaining lumbar stability,relieving clinical symptom.It is a good curative method for lumbar vertebrae instability.
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[Objective]To observe the effect of Solis cage made of polyether ether ketone(PEEK)for the cervical interbody fusion after anterior discoidectomy of two levels cervical spondylotic myelopathy.[Method]We retrospectively analyzed the clinical outcome of 16 patients with two levels cervical spondylotic myelopathy underwent anterior discoidectomy and stabilized the operative segment using Solis cage from September 2002 to September 2004.Sequent X-ray examination was taken after operation to observe the stability and fusion of the operative segments.[Result]All of the segments were mobilized at the next day after operation.The patients were followed up from 14 months to 36 months(averaged 18 months).The operative segments were stable instantly and solid fusion was observed at 3 to 6 months after operation.15/16 of patients were satisfactory,no complication was found.[Conclusion]The immediate stability of the operative segments can be obtained by Solis cage,the Solis cage is safe and simple,complication is relatively few.It has a special advantage in the treatment of the discontinuous two levels cervical spondylotic myelopathy.
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[Objective]To observe the degradation process of PDLLA in the intervertebral fusion.[Method]Twenty goats were divided into 4 groups as experimental group,and their L_(3~4)intervertebal spaces were implanted with PDLLA cage containing pieces of graft bone.Animals were sacrificed at 4,8,12,16 wks and specimens were taken for observation of the degradation process and bone fusion by gross observation and electronic microscope.Another 12 goats were used as normal fusion control group.Their L_(3~4)space were grafted with bone block for fusion.[Result]The degradation rate was non-lineal.In the early stage of fusion,the main degradation and decrease of molecular weight was shown at the superficial decomposition.With the proceeding of fusion and degradation,as the kydrolyzation speeding-up,internal decomposition by self-catalyse resulted into the collapse and total disassemble of the PDLLA.The PDLLA cage maintained its shape in the early stage and its biomechanical strength decrease in late stage but was still enough to keep the structure from collapse,till the fusion was achieved in the bone implant area.[Conclusion]The velocity of degradation of PDLLA is slower than the speed of bone regeneration of bone fusion,so the PDLLA cage could provide sufficient support during the process of intervertebal fusion and is a suitable choice of degradative material for cage in the intervertebal fusion.
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Objective To evaluate the stability and compressive mechanical functions of the lumbar spine following insertion of a new self-made allograft interbody fusion cage.Methods Anti-bending intensity with three points test,anti-rotation intensity and compressive stiffness were measured at L4-L5 lumbar spine on five adult human fresh cadaveric specimens following insertion of a new self-made allograft interbody fusion cage and compared with that of before and after nucleus pulposus removal.Results The anti-bending intensity of flexion and extension of lumbar spine after inserting a new allograft interbody fusion cage was increased significantly(P
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OBJECTIVES: Of all fusion techniques in the lumbar spines, PLIF has the best theoretical opportunity in achieving spinal fusion by way of load sharing effect of the anterior column but it is taken to be a technically demanding procedure and frequent problems have been reported. Threaded Fusion Cage(TFC) has been used as a substitute for autologous bone grafts during posterior lumbar interbody fusion in degenerative lumbar diseases since 1992. The purpose of this study is to evaluate the long-term efficacy of TFC in achieving a spinal fusion and the clinical outcome. METHODS: Total 597 patients underwent PLIF with TFC using laminectomy bone chips as bone graft during the last 7 years. Among them, 351 patients could be followed-up for more than 3 years and their clinical and radiographic data were reviewed retrospectively. Total 497 segments of PLIF with TFC were done in those 351 patients, their mean follow-up period were 59.8+/-9.1 months. RESULTS: The clinical success according to Prolos scale were achieved in 83.2% of the patients. When observed according to the disease entities, however multiple spondylotic stenosis patients showed significantly less favorable outcome(p<0.05). In the radiologic evaluation, bony fusion was achieved in 92.0% but when observed according to the disease entities, the fusion rate was significantly lower in the spondylolytic spondylolisthesis patients(p<0.05). CONCLUSION: The PLIF with TFC has been found to be an effective and safe procedure for lumbar spine fusion, demonstrating a high fusion rate and clinical success with rare complications. In addition, using the laminectomy bone chips as the bone graft in the TFC seemed to provide successful bony fusion without further invasive and painful procedure to obtain iliac bone graft.
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Humans , Constriction, Pathologic , Follow-Up Studies , Laminectomy , Retrospective Studies , Spinal Fusion , Spine , Spondylolisthesis , TransplantsABSTRACT
For the primary fusion of adult's lumbar spondylolisthesis the authors performed either posterolateral fusion(PLF) with transpedicular screw fixation, or posterior lumbar interbody fusion(PLIF) with cages and transpedicular screw fixation, on 75 patients during five years between Jan. 1993 and Dec. 1997. The outcomes were retrospectively reviewed with emphasis on comparison of the results of these two surgical methods. Between patients treated with PLF(PLF group) and PLIF(PLIF group) there were no differences in distribution of preoperative variables such as patients' age and gender, type, level, grade of spondylolisthesis, and symptom durations. Mean follow-up period was 22.3 months in PLF group(n=44) and 17.4 months in PLIF group(n=31) (p<0.001). The rate of fusion was 85% in PLF group, and 94% in PLIF group(p=0.292). The postoperative outcome, expressed as mean follow-up score of Prolo scale, was 6.86 in PLF group and 7.42 in PLIF group(p=0.007). The variables that were associated with the outcomes were the level of spondylolisthesis(p=0.001) and the type of fusion (p=0.023). Variables such as age, gender, type and grade of spondylolisthesis, preoperative symptom duration, radiological findings of fusion status, change in disc height, and change in sagittal angle were not associated with the outcomes. The complication rate was 11% in PLF group and 19% in PLIF group. Overall successful results, defined by 7 or more in follow-up score of Prolo scale, were seen in 68% of PLF group and 87% of PLIF group(p=0.098). It is concluded that better surgical outcomes were obtained by PLIF methods in adults with lumbar spondylolisthesis, but with regards to the incidence of complications, although mostly minor and reversible, was more frequent in PLIF group.